That loyal base is expected to carry Clinton to a sizable victory in the West Virginia primary tomorrow, though it will not do much to close the gap between her and Barack Obama, her rival for the Democratic presidential nomination.

Clinton's lingering candidacy highlights not just her strengths but also how difficult it has been for Obama to make inroads among some key Democratic constituencies.

Clinton made a brief afternoon visit to the home of Anna Jarvis, who is credited with founding Mother's Day 100 years ago. Clinton spoke to reporters afterward and told stories about women who have changed history by pressing for equal rights and breaking into male-dominated careers.

She highlighted her own mother's working-class upbringing and quoted from letters she said mothers have written her recently.

"Keep fighting," Clinton said, reading from one of those letters. "The fact is that you stood throughout the constant ups and downs of this race. You never wavered and you never gave up."

Clinton said her favorite letter ended, "It's not over until the lady in the pantsuit says it is."

Clinton has promised to improve federal support for working mothers, including tax credits for child care and family leaves.

Though Obama has amassed a nearly insurmountable lead in delegates and has turned his attention to a general election against John McCain, the presumptive Republican nominee, Clinton is pressing ahead in West Virginia and Kentucky - states where the demographics strongly favor her.

Overall, her campaign has remained alive largely because of her 60 percent to 36 percent edge over Obama among white women voters in the primaries so far. But among college-educated white women her edge is much smaller, 54 percent to 43 percent, according to exit polls conducted for the Associated Press and television networks.

Even if, as expected, she racks up hefty wins in both West Virginia and Kentucky, it probably will not change the landscape of the race. But Clinton's advisers hope it will persuade party leaders that she is more likely than Obama to beat McCain.

Clinton did not mention Obama yesterday. But campaign strategist Howard Wolfson said West Virginia is a key swing state that Republicans won in 2000 and 2004, and that Clinton will put it back in the Democratic column.

In the overall race for the nomination, Obama has 1,864.5 pledged delegates and Clinton has 1,697, according to the latest Associated Press tally. Obama is 160.5 delegates shy of the 2,025 needed to secure the Democratic nomination.

Besides his lead in pledged delegates, those won in primaries and caucuses, Obama over the weekend erased Clinton's once-commanding advantage among superdelegates, the elected Democrats and party leaders who will play a role in determining which candidate becomes the nominee. Obama has endorsements from 276, and Clinton has 271.5.

Obama took a day off from campaigning yesterday, spending it at home in Chicago. He has scheduled campaign appearances in Charleston, W. Va., and Louisville, Ky., today.

Obama's campaign chief, David Axelrod, predicted yesterday that the long battle for the nomination will soon be over.

Appearing on "Fox New Sunday," Axelrod said undecided superdelegates to the party convention who will decide the nomination are opting for the senator from Illinois. "You're going to see people [superdelegates] making decisions at a rapid pace from this point on," he said.

Wolfson said that if Obama wants Clinton out of the race, he should "beat her in West Virginia, beat her in Puerto Rico, beat her in Kentucky," referring to three of the final six contests for the nomination, all of which favor Clinton.

But he said if Obama wins the nomination, the senator from New York will throw her support and resources behind him.

Many Democrats are eager to get the nominating battle over so the party can unite and prepare to face McCain. Some worry the protracted battle is hurting their chances in November by highlighting both candidates' weak points and driving a wedge between their supporters.